HomeMy WebLinkAboutObservation of ExcavationKumar & Associates, Inc.® 5020 County Road 154
K Geotechnical and Materials Engineers Glenwood Springs, CO 81601
and Environmental Scientists phone: (970) 945-7988
email: kaglenwood@kumarusa.com
—� www.kumarusa.com
An &YgAoy" moaned Company
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
July 17, 2025
Precision Built
Attn: Brent Ritter
8106 County Road 117
Glenwood Springs, Colorado 81601
brentCc precision builtcm.com
Project No. 21-7-519.A
Subject: Observation of Excavation, Proposed Residence, Lot H-16, Aspen Glen,
305 Saddleback Road, Carbondale, Colorado
Dear Brent:
As requested, a representative of Kumar & Associates, Inc. observed the excavation at the
subject site on July. 17, 2025 to evaluate the soils exposed for foundation support. The findings
of our observations and recommendations for the foundation design are presented in this report.
We previously conducted a subsoil study for design of foundations at the site and presented our
findings in a report dated August 10, 2021, Project No. 21-7-519.
The proposed residence will be two story wood frame structure over a crawlspace. Due to the
depth of clay soils encountered in the excavation, footings will be placed on up to about 4 feet of
compacted 3/-inch road base.
At the time of our visit to the site, the foundation excavation had been cut in one level from 7 to
8 feet below the adjacent ground surface. The soils exposed in the bottom of the trench
excavations consisted of stiff to very stiff, sandy silty clay. No free water was encountered in the
excavation and the soils were slightly moist to moist.
The soil conditions exposed in the excavation are consistent with those previously encountered
on the site and suitable for support of spread footings designed for the recommended allowable
bearing pressure of 2,500 psf on compacted structural fill. The structural fill will consist of 3/ -inch
road base compacted to at least 98% of the maximum Standard Proctor density. Loose and
disturbed soils should be removed in the footing areas to expose the undisturbed natural soils.
Other recommendations presented in our previous report which are applicable should also be
observed.
The recommendations submitted in this letter are based on our observation of the soils exposed
within the foundation excavation and the previous subsurface exploration at the site. Variations
in the subsurface conditions below the excavation could increase the risk of foundation
movement. We should be advised of any variations encountered in the excavation conditions for
possible changes to recommendations contained in this letter. Our services do not include
determining the presence, prevention or possibility of mold or other biological contaminants
(MOBC) developing in the future. If the client is concerned about MOBC, then a professional in
this special field of practice should be consulted.
Precision Built
July 17, 2025
Project No. 21-7-519.A
Page 2
If you have any questions or need further assistance, please call our office.
Sincerely,
Kumar &
Daniel E. Hardin, P.
DEH/kac
/ONAL�
Kumar & Associates, Inc